日夜(にちや)

にちや
adverb
day and night, constantly
1. day and night, constantly, always
Continuously without rest; working or occurring both day and night.
研究者(けんきゅうしゃ)たちは日夜(にちや)努力(どりょく)している。
The researchers are working hard day and night.
日夜(にちや)訓練(くんれん)を続(つづ)けている。
They continue training day and night.
工場(こうじょう)は日夜(にちや)稼働(かどう)している。
The factory operates around the clock.

日夜(にちや) emphasizes tireless, continuous effort — working or happening both day and night without pause.

COMPOUND: 日(にち) (day) + 夜(や) (night)

REGISTER:
Somewhat formal and literary. In casual speech, いつも or ずっと would be more natural.

COMMON PATTERNS:

  • 日夜(にちや)努力(どりょく)する: to make efforts day and night
  • 日夜(にちや)研究(けんきゅう)する: to research day and night
  • 日夜(にちや)稼働(かどう)する: to operate around the clock

SIMILAR EXPRESSIONS:

  • 昼夜(ちゅうや): day and night (similar meaning, slightly more neutral)
  • 四六時中(しろくじちゅう): around the clock, constantly (colloquial)
  • 絶(た)えず: constantly, unceasingly (more formal)

Related Words

Synonym: 昼夜(ちゅうや) (day and night)
general
Added 2026.1.11 21:36 · Revised 2026.4.7 14:23
03000/03130_nichiya